package com.example.demo.NiuKe.v06;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class Main {
    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        String str;
        while ((str = br.readLine())!=null){
            Double d = Double.valueOf(str);
            int count = 0;
            while (d>1.0){
               d--;
               count = count+1;
           }
           d = d *10;
            if(d<5){
                System.out.println(count);
            }else {
                System.out.println(count+1);
            }
        }
    }
}
